anyhow/
ptr.rs

1use alloc::boxed::Box;
2use core::marker::PhantomData;
3use core::ptr::NonNull;
4
5#[repr(transparent)]
6pub struct Own<T>
7where
8    T: ?Sized,
9{
10    pub ptr: NonNull<T>,
11}
12
13unsafe impl<T> Send for Own<T> where T: ?Sized {}
14
15unsafe impl<T> Sync for Own<T> where T: ?Sized {}
16
17impl<T> Copy for Own<T> where T: ?Sized {}
18
19impl<T> Clone for Own<T>
20where
21    T: ?Sized,
22{
23    fn clone(&self) -> Self {
24        *self
25    }
26}
27
28impl<T> Own<T>
29where
30    T: ?Sized,
31{
32    pub fn new(ptr: Box<T>) -> Self {
33        Own {
34            ptr: unsafe { NonNull::new_unchecked(Box::into_raw(ptr)) },
35        }
36    }
37
38    pub fn cast<U: CastTo>(self) -> Own<U::Target> {
39        Own {
40            ptr: self.ptr.cast(),
41        }
42    }
43
44    pub unsafe fn boxed(self) -> Box<T> {
45        unsafe { Box::from_raw(self.ptr.as_ptr()) }
46    }
47
48    pub fn by_ref(&self) -> Ref<T> {
49        Ref {
50            ptr: self.ptr,
51            lifetime: PhantomData,
52        }
53    }
54
55    pub fn by_mut(&mut self) -> Mut<T> {
56        Mut {
57            ptr: self.ptr,
58            lifetime: PhantomData,
59        }
60    }
61}
62
63#[repr(transparent)]
64pub struct Ref<'a, T>
65where
66    T: ?Sized,
67{
68    pub ptr: NonNull<T>,
69    lifetime: PhantomData<&'a T>,
70}
71
72impl<'a, T> Copy for Ref<'a, T> where T: ?Sized {}
73
74impl<'a, T> Clone for Ref<'a, T>
75where
76    T: ?Sized,
77{
78    fn clone(&self) -> Self {
79        *self
80    }
81}
82
83impl<'a, T> Ref<'a, T>
84where
85    T: ?Sized,
86{
87    pub fn new(ptr: &'a T) -> Self {
88        Ref {
89            ptr: NonNull::from(ptr),
90            lifetime: PhantomData,
91        }
92    }
93
94    pub fn from_raw(ptr: NonNull<T>) -> Self {
95        Ref {
96            ptr,
97            lifetime: PhantomData,
98        }
99    }
100
101    pub fn cast<U: CastTo>(self) -> Ref<'a, U::Target> {
102        Ref {
103            ptr: self.ptr.cast(),
104            lifetime: PhantomData,
105        }
106    }
107
108    pub fn by_mut(self) -> Mut<'a, T> {
109        Mut {
110            ptr: self.ptr,
111            lifetime: PhantomData,
112        }
113    }
114
115    pub fn as_ptr(self) -> *const T {
116        self.ptr.as_ptr().cast_const()
117    }
118
119    pub unsafe fn deref(self) -> &'a T {
120        unsafe { &*self.ptr.as_ptr() }
121    }
122}
123
124#[repr(transparent)]
125pub struct Mut<'a, T>
126where
127    T: ?Sized,
128{
129    pub ptr: NonNull<T>,
130    lifetime: PhantomData<&'a mut T>,
131}
132
133impl<'a, T> Copy for Mut<'a, T> where T: ?Sized {}
134
135impl<'a, T> Clone for Mut<'a, T>
136where
137    T: ?Sized,
138{
139    fn clone(&self) -> Self {
140        *self
141    }
142}
143
144impl<'a, T> Mut<'a, T>
145where
146    T: ?Sized,
147{
148    pub fn cast<U: CastTo>(self) -> Mut<'a, U::Target> {
149        Mut {
150            ptr: self.ptr.cast(),
151            lifetime: PhantomData,
152        }
153    }
154
155    pub fn by_ref(self) -> Ref<'a, T> {
156        Ref {
157            ptr: self.ptr,
158            lifetime: PhantomData,
159        }
160    }
161
162    pub fn extend<'b>(self) -> Mut<'b, T> {
163        Mut {
164            ptr: self.ptr,
165            lifetime: PhantomData,
166        }
167    }
168
169    pub unsafe fn deref_mut(self) -> &'a mut T {
170        unsafe { &mut *self.ptr.as_ptr() }
171    }
172}
173
174impl<'a, T> Mut<'a, T> {
175    pub unsafe fn read(self) -> T {
176        unsafe { self.ptr.as_ptr().read() }
177    }
178}
179
180// Force turbofish on all calls of `.cast::<U>()`.
181pub trait CastTo {
182    type Target;
183}
184
185impl<T> CastTo for T {
186    type Target = T;
187}
anyhow/ptr.rs

anyhow/
ptr.rs
